* lisp/gnus/gnus-sum.el: Use lexical-binding

(gnus-summary-make-menu-bar, gnus-summary-display-make-predicate)
(gnus-summary-refer-thread, gnus-summary-find-matching)
(gnus-summary-edit-article, gnus-summary-sort):
Replace backquoted lambda with closure.
(gnus-summary-article-header): Use define-inline rather than defmacro,
so it's also a function.
(gnus-save-hidden-threads, gnus-summary-iterate, gnus-with-article):
Use `declare`.
(gnus-thread-sort-by-random): Simplify.
(gnus-summary-display-article, gnus-summary-limit-to-address):
Hoist common code outside of `if`.
1 job for master in 58 minutes and 16 seconds (queued for 4 seconds)
Status Job ID Name Coverage
failed #1770


Name Stage Failure
test-all Test
Makefile:318: recipe for target 'check-doit' failed
make[2]: *** [check-doit] Error 1
make[2]: Leaving directory '/builds/emacs/emacs/test'
Makefile:293: recipe for target 'check-expensive' failed
make[1]: *** [check-expensive] Error 2
make[1]: Leaving directory '/builds/emacs/emacs/test'
Makefile:957: recipe for target 'check-expensive' failed
make: *** [check-expensive] Error 2
ERROR: Job failed: exit code 1